1. Historical versus Current Distribution. In the United States, Texas toads
(Bufospeciosus) are distributed throughout the western 2/3 of Texas,
west into southeastern New Mexico, and north into western Oklahoma, including the
panhandle (McAllister and Trauth, 1993; Killebrew et al., 1995; Dixon, 2000). The
distribution of Texas toads has not changed as dramatically as other Bufo species
throughout the United States (J. Dixon, personal communication).

2. Historical versus Current Abundance. Brown (B.C., 1950) reported that Texas
toads are one of Texas’ most abundant toads. However, data on changes in
abundance of Texas toads over their entire range do not exist. Dixon (2000) reports
that populations of Texas toads in the Rio Grande Valley, Texas, are declining due to the
heavy use of pesticides and herbicides on agricultural lands. The decline of Texas
toads in the Rio Grande Valley is somewhat alarming, as Texas toads represent one of the
most abundant toads in the region (Thorton, 1977). Population trends of Texas
toads in southeast New Mexico appear stable (C.W.P., personal observations).

3. Life History Features.

A. Breeding.
Reproduction is aquatic.

i. Breeding migrations. Adults aggregate at temporary pools within a few hours
after a rain event. Breeding males call any time of day for up to 4 d after a rain
event, calling most intensely at night (Moore, 1976; G.H.D., unpublished data).
Males call while clinging to partially submerged vegetation or in the shallow regions of
the breeding site. Their call consists of a continuous series of explosive trills,
each lasting approximately 1.5 s, given at intervals of about 1 s (Stebbins, 1985).
Axtell (1958) reported that calling males were “passive in their relationship with
the females until they approached and made body contact.” Axtell (1958) also
reported that females preferred the loudest calling male (also the largest) over smaller
individuals in the vicinity.

i. Egg deposition sites. Eggs are typically deposited around the base of submerged
vegetation. Multiple pairs will deposit eggs around the same clump of grass.

ii. Clutch size. Eggs are brown and yellow, crowded (14–20 eggs/30 mm), about
1.4 mm in diameter, and hatch in 2 d (Wright and Wright, 1949). There are no data
on clutch size for Texas toads. However, the clutch of an average sized Great
Plains toad (Bufocognatus), closely related to Texas toads, is about
11,000 eggs (Krupa, 1994); this number could be used as an estimate until data on Texas
toads are available.

C.
Larvae/Metamorphosis.

i. Length of larval stage. The tadpole stage lasts from as few as 18 d (Moore,
1976) to approximately 60 d (Wright and Wright, 1949).

ii. Larval requirements.

a. Food. Tadpoles scrape algae off of submerged vegetation and substrate.
There are no data on the specific dietary preference of Texas toad tadpoles.

b. Cover. Cover may be aquatic vegetation or rocky substrate, although this may
vary from site to site. When startled, tadpoles will often retreat to deeper areas
within the pool.

iii. Larval polymorphisms. Have not been documented.

iv. Features of metamorphosis. Studies have reported time to metamorphosis from 18
d–60 d (Wright and Wright, 1949; Moore, 1976). Thus, timing and duration of
metamorphosis varies depending upon site characteristics (i.e., water temperature,
presence of predators, densities, and resource availability).

v. Post-metamorphic migrations. Recently metamorphosed toadlets usually remain
near the natal pool until the pool has dried (Degenhardt et al., 1996). No data are
available on migration distance; however, dispersal is likely correlated to the proximity
of suitable adult habitat. Moore (1976) monitored the growth of recently
metamorphosed toads for 7 mo in southern Texas. He calculated a growth rate of
approximately 10 mm/mo, which indicates that toads born early in the breeding season
would reach sexual maturity in time to breed the following year. Toadlets will
burrow into the soil, take refuge in mud cracks, or retreat beneath vegetation and other
cover to prevent desiccation.

D. Juvenile
Habitat. Although Texas toads burrow, they also utilize habitat beneath rocks and
in mud cracks and gopher burrows (Wilks, 1963; G.H.D., personal observation). The
critical habitat characteristics for juvenile Texas toads are likely similar to those of
the adults, i.e., high water retention in soils and/or relatively high humidity in refuge
sites.

E. Adult
Habitat. Texas toads are a desert species found in association with permanent
streams, irrigation ditches, watering tanks, and ephemeral pools (Jameson and Flury,
1949; Wright and Wright, 1949; Dayton, 2000a). They are found in grassland, open
woodland, and mesquite-savanna habitats. Texas toads prefer sandy soils, where they
burrow. However, they are associated with soils that are frequently inundated and
have a relatively high percentage of clay (Dayton, 2000a). Habitat characteristics
for adults are likely similar to those of juveniles. It is crucial for adults to
take refuge in sites with relatively high humidity and/or water holding capacity to
prevent desiccation during dry periods that can last for several months.

M. Longevity.
The life span of Texas toads in the wild is unknown. However, a wild-caught
specimen was kept in the Philadelphia Zoo for 4 yr, 3 mo. Sex and age at the time
of capture of this individual was unknown (Bowler, 1977).

N. Feeding
Behavior. Texas toads are opportunistic feeders that take a diverse array of
terrestrial and flying arthropods (Degenhardt et al., 1996). The stomach contents
from one individual included hemipterans, coleopterans, and hymenopterans (Malone,
1999).

4. Conservation. Although historical data on the abundance and distribution of
Texas toads over their entire range do not exist, population and abundance trends
throughout the majority of their range appear to be stable (J. Dixon, personal
communication; C.W.P. personal observations). Declines have been observed in
agricultural areas in southern Texas where pesticide and herbicide use is heavy (Dixon,
2000). Texas toads can be locally abundant and do not seem to be undergoing the
dramatic declines that are being observed for some of the other amphibian species in
North America.